Webcit works best with a recent, standards complaint browser. New features take advantage of the full range of DOM, JavaScript and CSS features.
In particular, the following versions have been tested against during development:

Internet Explorer does not yet fully implement the features present in various standards in a way consistent with those above, such that various Webcit features (in particular, mailbox view and task list) do not work as well.

Versions 6 and later of Internet Explorer are supported with reduced functionality.